Exhaustive Endurance Exercise Research Articles

Reproductive Profile of Physically Active Men After Exhaustive Endurance Exercise

Reproductive Profile of Physically Active Men After Exhaustive Endurance Exercise

Reproductive Profile of Physically Active Men After Exhaustive Endurance Exercise

The purpose of this study on non-professional (recreational) athletes was two-fold: 1) to determine if endurance exercise (EE) routinely used by professional athletes would produce reproductive changes in the general population, and 2) to assess reversion. Short-term exhaustive endurance exercise (EEE) can produce alterations in the hypothalamic-pituitary-gonadal (HPG) axis with subsequent fertility changes. Sixteen healthy adult male volunteers were divided into experimental (8) and control (8) groups for the exercise period. A cycloergometer provided EEE for a period of 2 weeks. The experimental group exercised four times a week; controls were without EEE. The hormonal and seminological profiles of all subjects were evaluated. Two weeks of EEE produced hormonal and seminological values in the experimental group that were statistically different from their own pre-treatment values (FSH: 3.33 +/- 1.7; LH: 3.73 +/- 1.36; sperm concentration/ml: 42.50 +/- 29.46; type a velocity: 25.23 +/- 10.9; type d velocity: 46.18 +/- 15.81; % of normal forms: 10.42 +/- 1.97) as well as from the pre- and post-treatment control group values. The measured parameters almost returned to pre-treatment levels in the experimental group 2 - 3 days after EEE ended. From this study we concluded that when subjected to EEE, individuals drawn from a recreational exercising life style experienced changes similar to those observed in studies done with athletes, and short-term EEE induced a reversible alteration to the HPG axis.

Differential Expression of a Newly-Discovered Phylogenetically Conserved HIF1alpha mRNA Variant

Exhaustive endurance exercise and especially intensive training under high altitude conditions have an impact on the supply of diverse tissues and cell types with oxygen. In most cells the expression of the transcription factor HIF1? mediates the expression of genes with cell protective function. HIF1α is therefore an important marker for the dimension of exercise induced cell protection. PURPOSE: Here we investigated the differential expression of a new potential HIF1α mRNA variant. METHODS: Expression of a newly-discovered, HIF1α mRNA variant with an extended 3'UTR (HIF1α-1) was investigated by 3'RACE followed by sequencing. Differential expression of HIF 1α–1 and the classic HIF1α mRNA variants was quantified by real-time RT-PCR in lymphocytes following a half-marathon run and in peripheral mononuclear cells following normobaric hypoxia (12,5% FiO2). RESULTS: HIF1α-1 has a more than 2000 bp longer 3'-untranslated region than the mRNA variants, which have already been described. A sequence comparison between human, mouse and rat demonstrates a high phylogenetic conservation of the 3'-untranslated end of HIF1α-1, indicating a functional relevance. HIF1α-1 is in contrast to the other variants significantly 3.3-fold up-regulated in isolated lymphocytes of half-marathon runners following competition (n = 7, CI: 1,9 – 5,8; p=0.002). Normobaric hypoxia did not have an influence on HIF1α-1. CONCLUSION: HIF1α-1 is in contrast to the other variants entirely complementary to the potent HIF1α down-regulator Anti-HIF1α-mRNA. We propose that HIF1α-l is one of the factors which contribute to a complex regulation of HIF 1α expression on a posttranscriptional level.

L-Carnitine and the recovery from exhaustive endurance exercise: a randomised, double-blind, placebo-controlled trial

We hypothesised that L: -carnitine could accelerate recovery from exhaustive exercise since increased blood L: -carnitine concentrations elicit a vasodilation in isolated animal vessels as well as in patients with peripheral vascular or coronary artery disease during exercise. Twelve subjects received either 2 g L: -carnitine or a placebo in a study which was double-blind and crossover in design. Two hours after administration, the subjects performed a constant-load exercise test (CET(1)) cycling at their individual anaerobic threshold to exhaustion. Three hours later this test was repeated (CET(2)). After 4-14 days, each subject performed the same cycling tests after having taken the other substance. Exercise times of the 12 subjects were identical with L: -carnitine (CET(1): 21.3+/-5.7 min; CET(2): 21.4+/-5.3 min) and placebo (CET(1): 21.9+/-6.2 min; CET(2): 20.4+/-4.8 min). Also, heart rate, oxygen consumption, respiratory exchange ratio, and blood lactate concentration were identical. In conclusion, 2 g of L-carnitine taken 2 h before a first of two constant-load exercise tests had no influence on the second tests performed 3 h after the first test compared with placebo.

Skeletal muscle pathology in endurance athletes with acquired training intolerance

Background: It is well established that prolonged, exhaustive endurance exercise is capable of inducing skeletal muscle damage and temporary impairment of muscle function. Although skeletal muscle has a remarkable capacity...

Effect of Different Types of Carbohydrate Supplementation on Glycogen Supercompensation in Rat Skeletal Muscle

The purpose of this study was to examine the effects of glucose and sucrose supplement on glycogen accumulation in rat skeletal muscle and liver after exhaustive endurance exercise. Four- to five-week-old male Sprague-Dawley rats with an initial body weight ranging from 90 to 110 g were used for this study. All rats were trained by using a 7-day-long swimming exercise program, during which rats swam 6 h/day in two 3-h bouts separated by 45 min of rest. On the next day of the last training, all trained animals performed 240 min of swimming exercise with a weight equivalent to 3 % of their body weight to deplete muscle and liver glycogen. After glycogen-depleting exercise, rats were given a rodent chow diet plus either 5 % sucrose (SUC), 5 % glucose (GLU) or water (CON) for 6 h or 24 h. Despite equal amount of carbohydrate intake, glycogen concentration in rat epitrochlearis muscle of the GLU group rats was significantly higher compared with those observed in the CON (p<0.001) and the SUC groups (p<0.01). No significant difference in liver glycogen was observed among three groups. These results indicate that glucose supplementation rather than sucrose supplementation efficiently promotes glycogen supercompensation in rat skeletal muscle.

The Effect of Repeated Bouts of Exhaustive Endurance Exercise on Blood Lipid and Lipoprotein Profiles

The Effect of Repeated Bouts of Exhaustive Endurance Exercise on Blood Lipid and Lipoprotein Profiles

The Effect of Repeated Bouts of Exhaustive Endurance Exercise on Blood Lipid and Lipoprotein Profiles

The Effect of Repeated Bouts of Exhaustive Endurance Exercise on Blood Lipid and Lipoprotein Profiles

Effects of Exhaustive Endurance Exercise on Pulmonary Gas Exchange and Airway Function in Women.

Effects of Exhaustive Endurance Exercise on Pulmonary Gas Exchange and Airway Function in Women.

Effects of exhaustive endurance exercise on pulmonary gas exchange and airway function in women.

Seventeen fit women ran to exhaustion (14 +/- 4 min) at a constant speed and grade, reaching 95 +/- 3% of maximal O(2) consumption. Pre- and postexercise lung function, including airway resistance [total respiratory resistance (Rrs)] across a range of oscillation frequencies, was measured, and, on a separate day, airway reactivity was assessed via methacholine challenge. Arterial O(2) saturation decreased from 97.6 +/- 0.5% at rest to 95.1 +/- 1.9% at 1 min and to 92.5 +/- 2.6% at exhaustion. Alveolar-arterial O(2) difference (A-aDO(2)) widened to 27 +/- 7 Torr after 1 min and was maintained at this level until exhaustion. Arterial PO(2) (Pa(O(2))) fell to 80 +/- 8 Torr at 1 min and then increased to 86 +/- 9 Torr at exhaustion. This increase in Pa(O(2)) over the exercise duration occurred due to a hyperventilation-induced increase in alveolar PO(2) in the presence of a constant A-aDO(2). Arterial O(2) saturation fell with time because of increasing temperature (+2.6 +/- 0.5 degrees C) and progressive metabolic acidosis (arterial pH: 7.39 +/- 0.04 at 1 min to 7.26 +/- 0.07 at exhaustion). Plasma histamine increased throughout exercise but was inversely correlated with the fall in Pa(O(2)) at end exercise. Neither pre- nor postexercise Rrs, frequency dependence of Rrs, nor diffusing capacity for CO correlated with the exercise A-aDO(2) or Pa(O(2)). Although several subjects had a positive or borderline hyperresponsiveness to methacholine, this reactivity did not correlate with exercise-induced changes in Rrs or exercise-induced arterial hypoxemia. In conclusion, regardless of the degree of exercise-induced arterial hypoxemia at the onset of high-intensity exercise, prolonging exercise to exhaustion had no further deleterious effects on A-aDO(2), and the degree of gas exchange impairment was not related to individual differences in small or large airway function or reactivity.

Supramaximal flow in asthmatic patients

The use of noninvasive techniques to measure respiratory muscle performance after different types of endurance exercise has not been entirely successful, as the results have not consistently indicated diminished performance for similar types of exercise. The aim of the present study was 1) to compare different, noninvasive methods to assess respiratory muscle performance before and after an exhaustive cycling endurance test (which has previously been shown to induce diaphragmatic fatigue) and 2) to determine which of the tests best reflect published results of measurements of diaphragmatic fatigue. Twelve healthy subjects participated in the study and performed three different test series in a random order on three different days. These tests were performed before, and 5, 40 and 75 min after an exhausting task (a cycling endurance run at 85% of maximal oxygen uptake (V9O2,max)). The tests of the three test series were 1) breathing against a constant inspiratory resistance to task failure, 2) determination of 12-min sustained ventilatory capacity, and 3) spirometric and maximal inspiratory and expiratory mouth pressure measurements. The only measurement that was affected by exhaustive cycling was the time to task failure breathing against inspiratory resistance. It was significantly reduced from (mean+/-sD) 364+/-88 s before exercise to 219+/-122 s at 5 min after cessation of exercise. It is concluded that the constant-load resistive breathing test to task failure is the only noninvasive respiratory muscle performance test evaluated in this study which shows a decrease in respiratory muscle performance after exhaustive endurance exercise.

Exercise, immunology and upper respiratory tract infections.

The literature reveals a paradoxical response of the immune and host defense systems to endurance exercise apparent stimulation following long-term regular training and suppression in response to acute exposure to exhaustive endurance exercise. Several epidemiological surveys have confirmed a clinical manifestation of immunosuppression in the form of increased incidence of upper respiratory tract infection symptoms following participation in competitive marathon and ultramarathon running events. Prerace training status and racing intensity have been related to the incidence of this symptomatology during the postrace fortnight. Nutritional intervention studies have shown the antioxidant nutrient, vitamin C, to be effective in reducing the incidence of upper respiratory tract infection symptoms following competitive distance events. Laboratory studies have revealed this vitamin to be the first line of defense in neutralizing the auto-oxidative activity of phagocytes. It is hypothesized that exercise-induced neuroendocrine stimulation of the oxidative burst in neutrophils increases the rate of release of reactive oxygen species and that these are, in turn, neutralized by high plasma ascorbate levels. Enhancing intrinsic antioxidant defense by increasing exogenous antioxidant intake is thus theorized to be of long-term benefit to serious endurance athletes engaged in heavy training and competition.

Effects of exhaustive endurance exercise and its one-week daily repetition on neutrophil count and functional status in untrained men.

Whereas endurance exercise is known to induce marked neutrophilia, it remains to be fully understood as to whether the cell functions are altered as well as whether the adaptability of the responses to training occurs. To address both of these issues, we undertook the present longitudinal investigation in ten healthy untrained men (20-24 years, VO2max 39.1 +/- 4.2 ml/kg/min). The exercise protocol was 7 consecutive sessions of the same workload performed each day for 1.5 h at an intensity of 70% of VO2max. Peripheral blood samples were obtained before, immediately after, and 1 h after exercise on Days 1, 4, and 7, and served for determination of total and differential leukocyte counts, chemotaxis and chemiluminescence of neutrophils. Acute endurance exercise caused marked peripheral neutrophilia with significant increase in both absolute number and relative proportion of band neutrophils (p < 0.01, respectively), indicating partial recruitment of bone marrow neutrophils. While chemotaxis remained unaltered following exercise, reactive oxygen species generation of neutrophils, measured by luminol-dependent chemiluminescence upon stimulation with opsonized zymosan, was not only significantly enhanced following exercise (p < 0.01), but also associated with the proportional increase in band neutrophils (r = 0.727, p < 0.05), suggesting that neutrophils mobilized from the bone marrow following endurance exercise may possess higher responsiveness. On the other hand, the magnitude of the exercise-induced changes was reduced gradually by daily repeated exposure to endurance exercise, but none of the trends were significant except the decline in resting segmented neutrophil counts (p < 0.05) at least during a 1-wk period of repeated exercise sessions.

Strenuous exercise and immunological changes: a multiple-time-point analysis of leukocyte subsets, CD4/CD8 ratio, immunoglobulin production and NK cell response.

This study was designed to examine the impact of exhaustive endurance exercise on a number of immune parameters of physically fit male subjects (VO2max 66.5 +/- 5.3 ml/min/kg) who performed treadmill exercise at 65% of their VO2max for 120 min. Serial blood samples were taken before, during and after exercise and changes in leukocyte and lymphocyte subset concentrations; immunoglobulin production in vitro; and natural killer (NK) cell response were measured. The exercise regimen was found to induce the well-known phenomenon of leukocytosis which consisted primarily of a granulocytosis and lymphocytosis. Among the lymphocyte subsets, peripheral pan T cells (CD3+) as well as helper (CD4+) and suppressor (CD8+) T cells were found to be elevated. A relatively smaller increase in CD4+ than CD8+ cells resulted in depressed CD4/CD8 ratios throughout the exercise period. After exercise, T cells declined progressively and, 2 h post-exercise, were less than 60% of their pre-exercise level. In contrast, the CD4/CD8 ratio demonstrated a progressive increase, thus representing a reversal in the pattern observed during exercise and a trend towards an elevated ratio during recovery. B cells (CD19+) were relatively unaffected by exercise, although IgM production by pokeweed mitogen-stimulated lymphocytes obtained from blood samples after 120 min of exercise was significantly depressed. NK cells were affected dramatically by exercise. Both CD16+ cell numbers and NK cytotoxicity were increased during exercise, followed by a persistent depression in the post-exercise period. The strenuous exercise induced profound effect on NK cells as evidenced by a 40% depression of the NK cell count for as long as 7 days after the cessation of exercise. Our results provide direct kinetic evidence demonstrating that exhaustive exertion alters both lymphocyte distribution pattern and effector function, suggestive of possible exercise-induced immune compromise, particularly in the post-exercise recovery period.

Influence of Exhaustive Endurance Exercise on the Generation of Lipid Peroxides Post Exercise

Influence of Exhaustive Endurance Exercise on the Generation of Lipid Peroxides Post Exercise

Alterations of regular and mature monocytes are distinct, and dependent of intensity and duration of exercise

Circulating monocytes comprise functionally distinct regular (CD14bright+) and mature (CD14low+) cells. Cell surface receptors were determined by three colour flow cytometry in 8 healthy control subjects. Compared to regular monocytes, mature monocytes had lower levels of the high affinity Fc gamma receptor 1 (CD64), complement receptor 3 (CD11b), CD45RO and higher levels for HLA-DR, LFA-1 (CD11a/CD18), interleukin-2 receptor (CD25), CD45RA and the Fc gamma receptor 3 (CD16). Both regular and mature monocytes were measured before and up to three hours after four different types of exercise (Ex) in endurance trained athletes (n = 9-16). Immediately after anaerobic exercise of 1 min with a maximal lactate concentration (la max) of 12.3 (SD 1.4) mmol.1-1 and exhaustive exercise of 24 (SD 8) min with a maximal lactate concentration (lamax) of 7.4 (SD 2.6) mmol..-1 mature monocytes increased more than regular monocytes. Exhaustive endurance exercise of 87 (SD 21) min [lamax 3.7 (SD 1.0)] led to a similar increase of regular and mature monocytes. 15-33 min after a 100km run regular monocytes increased significantly, whereas mature monocytes decreased. Up to three hours after the end of all exercises mature monocytes fell below pre-exercise values. In conclusion, duration and intensity of exercise alter distinct maturation stages of monocytes differently. It is probable that the avidity of adhesion molecules like LFA-1 to their endothelial ligands is increased to enable the firm attachment to the endothelium.

Effects of anabolic steroids and endurance exercise on cardiac performance.

This study examined the effects of anabolic steroids and exhaustive endurance exercise, and the combination of both treatments on in vitro cardiac contractile function. Fifty-two male Sprague-Dawley rats were randomly assigned, in groups of 13, to one of the four groups: sedentary control (C), steroid-treated (ST), exercise-trained (E), and exercise plus steroid treated (E+S). Nandrolone decanoate was administered to the steroid-treated groups every 7-9 days during the 10 weeks study, while the C and E groups received glycerol injection on these occasions. The exercised rats ran on a treadmill wearing a collar weight (2-3% of body weight) for 50 min, 5 days a week. In vitro ventricular performance was assessed in isolated Langendorff perfused hearts in response to increasing left ventricular balloon volumes. Left ventricular +dP/dt, dP/dt at 60 mmHg developed pressure, tension time index, and Emax (slope of the pressure-volume curves) were significantly (p < 0.05) lowered in the E+S group, as compared to the C, E, or ST group. Meanwhile, the E group exhibited a higher (p < 0.05) left ventricular systolic pressure (LVSP) than the C and E+S groups. No significant differences in dP/dt/P, heart weight (wt), and heart wt to body wt ratio were detected among the four groups. Rats subjected to endurance exercise or anabolic steroid treatment alone exhibited no change in LV function.(ABSTRACT TRUNCATED AT 250 WORDS)

Dietary supplementation of vitamin E protects heart tissue from exercise-induced oxidant stress.

Exhaustive endurance exercise in adult female albino rats (C-Ex) increased the generation of free radicals (R.) in the myocardium, probably through enhanced oxidative mechanisms. Free radical mediated lipid peroxidation measured in the form of tissue MDA content also increased in C-Ex animals, suggesting the exercise-induced oxidative stress in these animals. Dietary supplementation of Vit E, for a period of 60 days significantly increased Vit E incorporation into the serum and myocardium, more so in the myocardium. Vit E supplementation to exercising animals completely abolished the radical production. The protection of Vit E against oxidative stress appears to be not mediated through the improvement of antioxidant mechanisms by enzymes like SOD, catalase and Se-GSH Px. However the non Se-GSH Px, the enzyme involved in the reduction of endoperoxides increased significantly in control and Vit E fed animals in response to exercise. The protection of Vit E against exercise-induced oxidative stress was correlated with its multivarious activities like a) scavenger of free radicals; b) inhibition of lipoxygenases; and c) reduction of peroxides in association with lipoxygenases. These studies indicate that dietary supplementation of Vit E protects the animals from the possible oxidative damages of endurance exercise.

Effects of Long-Endurance Running on Immune System Parameters and Lymphocyte Function in Experienced Marathoners

The extent and duration of changes in leukocyte subsets, lymphocyte subpopulations, spontaneous blastogenesis, cortisol, and catecholamines were measured in ten experienced marathoners, who ran 3 h to exhaustion in a laboratory setting. Blood samples were taken at baseline, 1 h of exercise, and 5 min, 1.5 h, 6 h, and 21 h of recovery. The 3-h endurance run was associated with significant leukocytosis, granulocytosis, neutrophilia, monocytosis, and eosinopenia during recovery. All of these parameters except for eosinophils returned to normal by 21 h of recovery. Total lymphocyte count increased 31% at 1 h of exercise, then decreased 19% at 1.5 h of recovery when compared with baseline values. T cell count showed no significant changes, but B cell lymphocytosis was measured at 5 min and 6 h of recovery. T helper/T suppressor ratio (H/S) was significantly elevated 39% at both 1.5 h and 21 h of recovery due to the decrease in number of T suppressor cells. Spontaneous blastogenesis was significantly increased 52% by 1 h of exercise and remained elevated throughout recovery. The increase in cortisol from baseline to 1.5 h of recovery correlated positively with the increase in both total leukocyte count (r = 0.78, P = 0.008) and granulocyte count (r = 0.81, P = 0.005). Our results suggest that exhaustive endurance exercise in marathon runners is associated with many significant perturbations in immune system parameters, most of which return to normal levels at 21 h of recovery.

β-Endorphin, Catecholamines, and Cortisol During Exhaustive Endurance Exercise*

To assess changes of beta-endorphin during intense endurance exercise, ten nonspecifically trained volunteers (aged 25.7 +/- 2.9 years) were subjected to an exhaustive endurance test on a cycle ergometer at the work load of the individual anaerobic threshold (IAT) determined in a preparatory graded exercise test. Prior to, in 25-min intervals during, and repeatedly subsequent to exercise venous blood samples were drawn to measure the levels of beta-endorphin (beta-E), cortisol (C), adrenaline (A), and noradrenaline (NA). In addition, lactate, heart rate, and rate of perceived exertion were determined. The levels of beta-E remained unchanged during the first 50 min; between the 50th and 75th min beta-E increased by 82% (p less than 0.01). At the end of the exercise (mean exercise time: 89 min), a beta-E level three times the resting level was measured. The maximum exercise-induced increase of beta-E showed a positive correlation to endurance capacity (W.kg-1 of IAT): r = 0.74; p less than 0.05. C exhibited similar changes to beta-E, but the onset of increase was delayed if compared with beta-E; there was a close correlation between these two stress hormones (75th min of exercise: r = 0.91; p less than 0.001). The catecholamines A and NA increased linearly during exercise, without a correlation with the behavior of beta-E being established.